Filtered connector

ABSTRACT

Electrical connector including low-pass filter contact units formed by inductance means of ferromagnetic material and capacitance sleeve means of dielectric material on a central conductive portion; the capacitive sleeve means is preferably approximately the same diameter as the end portions of the contact unit to provide a relatively thin unit while obtaining highly effective filtering. The units are readily assembled and each unit is independently removable from and re-installable in a contact passage of a support body. Curved tines extend inwardly from openings in a common ground plate to wipingly engage arcuately spaced portions of an outer conductive sleeve during installation and removal, insuring excellent electrical contact. Preferably, the contact plate is of a thin resilient metal and is engaged by one or two backing plates.

[ 1 Dec. 10, 1974 FILTERED CONNECTOR [751 Inventors: Jeff Tuchto, DonMills, Ontario;

Eugene S. Joseph, Scarboro, Ontario, both of Canada [73] Assignee: TheBunker-Ramo Corporation,

Oak Brook, Ill.

22 Filed: Nov. 6, 1972 21 Appl. No.: 303,713

Related US. Application Data [63] Continuation of Ser. Nos. 55,939, July17, 1970, abandoned, and Ser. No. 860,175, Sept. 19, 1969, abandoned,and Ser. No. 584,745, Oct. 16, 1966,

abandoned.

[52] U.S.Cl. 333/79, 339/59 M, 339/147 R, 339/207 R, 339/210 M [51] Int.Cl H03h 7/04, H01r 13/66 [58] Field of Search 333/79; 339/59 M, 147 R,339/210 M, 207 R OTHER PUBLICATIONS Rowlands et a1., suppressing Noiseat the Connector," Electronics, 5-17-65, pp. 65-67.

.Primary Examiner-James W. Lawrence Assistant Examiner-Wm. H. PunterAttorney, Agent, or FirmDavid R. Bair; F. M. Arbu'ckle 5 7 ABSTRACTElectrical connector including low-pass filter contact units formed byinductance means of ferromagnetic material and capacitance sleeve meansof dielectric material on a central conductive portion; the capacitivesleeve means is preferably approximately the same diameter as the endportions of the contact unit to provide a relatively thin unit whileobtaining highly effective filtering. The units are readily assembledand each unit is independently removable from and reinstallable in acontact passage of a support body. Curved tines extend inwardly fromopenings in a common ground plate to wipingly engage arcuately spacedportions of an outer conductive sleeve during installation and removal,insuring excellent electrical contact. Preferably, the contact plate isof a thin resilient metal and is engaged by one or two backing plates.

13 Claims, 7 Drawing Figures I FILTERED CONNECTOR This application is acontinuation of our prior applications Ser. Nos. 55,939, filed July 17,1970; 860,175, filed Sept. 19, 1969; and 584,745, filed Oct. 16, 1966,all abandoned.

The present invention relates to a filtered connector.

A broad object of the invention is to provide a filtered connectorutilizing poke-home or removable contacts.

The connector is used in various installations such as, for example, ininstruments enclosed in a case or cabinet of conductive material, suchas aluminum. An external conductor or cable leads to the cabinet andconnects with the filtered connector and other conductor or conductorslead from the connector to components within the case. The case isgrounded, and means are provided for connecting the connector with thecase and thus grounding it. The connector filters out high frequencynoise which is diverted to ground, allowing only the direct current andlow frequency alternating current signals to pass through the connector.Heretofore there has not been a successful and practical filteredconnector utilizing removable contacts.

Another and broad object of the invention is to provide a filteredconnector of poke-home character which has extremely good electricalcharacteristics.

Another object is to provide a filtered connector of the foregoinggeneral character including pin contacts which can be easily and quicklyinserted in place and removed therefrom, and which can be so inserted agreat number of times without deletrious effects on the connector. 7

Other objects of the invention are to provide a filtered connector whichis extremely small and inexpensive.

Other objects and advantges of the invention will appear from thefollowing detail description taken in conjunction with the accompanyingdrawings in which:

FIG. 1 is a diagrammatic illustration of an instrument in which thefiltered connector of the present invention is incorporated, this figurealso showing the filtered connector itself;

FIG. 2 is a diagram ofa filtering means of known kind and which isincorporated in its essentials in the filtered connector of the presentinvention;

FIG. 3-is a diagram of the same filtering means of FIG. 2 but showing amodified arrangement of the elements and the specific arrangementincorporated in the connector of the present invention;

FIG. 4 is a perspective view of the main .support structure of thefiltered connector;

FIG. 5 is also a perspective view of the main support structure buttaken from the side opposite that of FIG.

FIG. 6 is a large scale sectional view taken at line 6-6 of FIG. 4 andalso including a fragment of the cabinet in which the connector ismounted; and

FIG. 7 is a faceview of the contact plate incorporated in the connector.

Referring now in detail to the drawings, attention is directed first toFIG. I which shows the connector of the invention incorporated in aninstrument, at least portions of which are shown diagrammatically. Theconnector is indicated as a whole at 10 mounted in a case or cabinet 12of conductive material such as aluminum, and grounded as indicated at14. An external conductor 16 which is usually in the form of a cabledetachably connects with the connector through a plug 18 in a knownmanner. Other conductors 20 are connected with the pin contacts of theconnector, as referred to below, and lead to various instrumentalitiesin the case 12.

The connector of the invention includes filtering means incorporatingthe essentials represented in FIG.

. 2 where the conductor 16 leads to an inductance means 24 and then tothe conductor 20 in the case. Capacitor means 25 are provided, includingcapacitors 26 and 28 connected with the conductors 16 and 20 and then toa common conductor 30 representing the case 12, and thereby to ground14.

The filtering means shown in FIG. 3 is essentially the same as that ofFIG. 2 but includes rearranged elements according to their arrangementin the connector of this invention. In the present instance, thecapacitor 26 includes a first plate 32, the capacitor 28 includes afirst plate 34, and the two capacitors together have a second and commonplate 36, these plates being identified in the connector in thedescription hereinbelow.

FIGS. 4, 5 and 6 show the details of the construction of the connector.For convenience the connector will be identified as including a mainsupport structure 38 and a plurality of pin contacts 40 removablymounted therein. The structure 38 includes an outer block 42 and aninner block 44 of dielectric material of known kind, preferablypolycarbonate. Between the blocks is a central plate or foil 46 of goodconductive material and preferably beryllium copper and of about .003inches in thickness. This plate or foil is interposed between a pair ofother plates 48 preferably of the same material but of substantiallygreater thickness. such as about .010 inch. The blocks 42, 44 and theplates 46, 48 are secured together in rigid assembly, as by housings orcasings 50, 52 surrounding the peripheries of the respective blocks andhaving flanges 54, 56 extending beyond the housings and secured togetheras by rivets for securing the elements mentioned together. The plates46, 48 also extend beyond the blocks 42, 44 and preferably to the edgesof the flanges 54, 56 and are gripped therebetween. The supportstructure 38 is mounted in an aperture 58 (FIG. 6) in the case 12 andsecured therein as by bolt-nut means 60 with the adjacent flange 56 ingood electrical contact engagement with the wall of the case 12 so as toeffectively ground the plate 46. Thus the plates 48 minimize theelectrical impedance and increase the mechanical support.

The housing 52 preferably extends beyond the block 42 and forms a socket62 for receiving the plug 18 of the cable, in the usual manner.

The structure 38 is provided with a plurality of through bores whichserve as apertures or pin cavities 64 removably receiving the pincontacts 40, as well as other bores such as 65A, the followingdescription however referring to the through bores 44 which arerelatively large in number and of uniform size. The central throughbores extend perpendicular to the lamina tion and of course form holesthrough all of the laminated elements. The size of the bores 64 relativeto the pin contacts 40 are of importance and will be referred to againhereinbelow. The bore 64 in the block 42 includes a radially inwardlyextending portion 67 and a counter-bore 68 at the front side of theblock opening to the front, forming a forwardly facing shoulder 70.Inwardly of the portion 67 is another counter-bore 72 forming aninwardly facing shoulder 74. The hole has still another counter-bore 76at its inner end extending to the adjacent plate 48 which also has ahole, 78, preferably of the same diameter as the counter-bore 76.

The hole in the block 44, designated 80, is of uniform diameter and ofthe same diameter as the counter-bore 72. The adjacent plate 48 has ahole 82 of the same diameter as the hole 80, and thus of smallerdiameter than the hole 78 in the opposite plate 48. The central plate 46also has a hole, 84, which is best shown in FIG. 7 which also shows theface of the central plate or foil 46. It also has holes 83 and 83Aaligned with holes of the blocks 42, 44 to form the aperture 67 of theapertures 66. Referring to the holes 84 these are formed by initiallycutting or punching them in the form of crosses, forming tines 86 whichare then depressed or bent out of the plane of the plate, and theyassume a shape calculated for producing a wiping action referred tobelow. That shape preferably is as indicated in FIG. 6 which isgenerally arcuate and preferably of a relatively long dimension inarcuate direction. It has been found that the greater the number oftines, the greater will be the effectiveness of the electrical contactbetween the tines and the pin contact.

The pin contact 40, removably disposed in each of various and selectedones of the apertures 64, as indicated, cooperates with the variousdimensions of the holes making up the aperture 64. The pin contact 40 ismade of good conductive material such as copper, which for manufacturingpurposes is made of two parts. The body includes a central reducedportion 90 and end portions 98 and 94. The end portion 98, or front end,is adapted for engagement with the plug on the conductor 16 while theend portion 94, which may also be considered to be a collar is connectedwith the conductor 20. The rear end portion 94 has a hole or socket 95into which the conductor 20 is inserted and is then crimped thereon forsecurement thereto.

The pin contact 40 at its forward end includes an enlargement or collar96 forwardly of which is another reduced portion 98 forming a pinreceived in the plug 18. A retainer clip 100 is fitted on the pin 98 andsecured thereto, adjacent to radially inwardly extending portion 67,having a radially yieldable, outwardly biased enlargement or bulbousportion 102.

After securing the conductor 20 to the pin contact 40, as indicated, thepin contact is inserted into the aperture from rear to front(right-to-left, FIG. 6), the retainer clip 100 collapsing or contractingin the portion 67 of the aperture, this movement continuing until thecollar 96 engages the shoulder 74, whereupon the bulbous portion 102passes by this restricted portion of the hole and expands, normally andyieldably retaining the pin contact in the aperture. Such a structureserves as a means for the insertion and removal of the pin contact andthe impedance elements from the passageway in the blocks 42 and 44 ofinsulating material without separation of the blocks.

The inductance means 24 identified in FIGS. 2 and 3 is shown in FIG. 6in the form ofa ferrule 104 of ferrite, preferably made up of aplurality of sections butted end-to-end. This ferrule surrounds thereduced central portion 90 and confined endwise between the collar 96and the rear end portion 94 which is secured to central portion 90 inany suitable manner such as by crimping. This ferrite ferrule producesan inductance in a known manner.

Outwardly of the ferrule 104 is a the capacitor means 25 identifiedabove which includes the plates 32, 34, and 36 and a dielectric sleeveor cylinder 106 that has a central through bore and is made of a rigidceramic material that is quite fragile. The plates are preferably ofsilver and may be a thin foil or coating applied to the inner and outersurfaces of the dielectric cylinder 106, the inner plates 32, 34being-spaced apart as indicated at 107 with end flanges 108 and 110engaging the body of the pin and specifically the collar 96 and rear endportion 94. The outer plate 36 is of substantial length and forms anouter exposed contact element for engagement with the tines 86.

The physical construction of the pin contact is such that, from thecollar 96 inwardly or rearwardly, it is substantially and effectively ofuniform diameter. The dimensions of certain of the elements representedin FIG. 6 are exaggerated, the plates 32, 34, 36 being of insignificantthickness from a physical standpoint although however, of complete anduniform electrical integrity. The diameter of this inner or rearwardlarge portion of the pin contact is only slightly less than the diameterof holes 80, 72 and in fact so dimensioned that the pin can be easilyinserted and removed by the hand, but not wobbling therein or havingappreciable play. As an example of the dimensions involved, the pincontact at its greatest diameter may be on the order of .085 inch, and.880 inch long.

The tines 86 extend inwardly beyond the diameter of the pin and uponinsertion of the pin into the aperture, the outer capacitor plate 36engages the tines with complete electrical contact therewith and toground. The dimensions of the holes 80, 72 are important from thestandpoint of physically positioning the pin contacts so that the pinelement 98 is received in the plug 18 readily and without bending ordistortion; it has the further advantage of establishing good electricalcontact between the outer capacitor plate 36 and the tines 86. Thecounter-bore 76 provides space for yield ing of the tines, but thiscounter-bore is of relatively small dimension axially. The tines 86being biased radially inwardly constantly engage the outer capacitorplate 36 at all times; they produce a good wiping action thereon forgood contact engagement, and the plurality of them circumferentiallyaids to the effectiveness of the contact engagement. The gripping of thecentral plate or foil 46 between the'plates 48, and particularly thefact that they do so throughout the entire area thereof, has been foundto produce an exceptional electrical conductive condition.

While a preferred form of the invention has been disclosed herein, itwill be understood that changes may be made therein within the spiritand scope of the appended claims.

What is claimed is:

I. In an electrical connector having a plurality of individuallyremovable and replaceable filtered contact units, a main support bodycomprising a pair of blocks of insulating material secured to each otherand having a plurality of aligned contact passages therethrough; andelectrical ground contact means comprising a planar layer of conductivematerial sandwiched between said pair of blocks and having openingsaligned with the passages in said blocks; each of said filtered contactunits including an elongated contact pin and filter means including acylinder of fragile dielectric material, said contact pin having a firstend portion adapted for connection with a mating connector member, asecond end portion adapted for connection with an electrical conductor,and an elongated central portion interconnecting said end portions; saidcylinder of fragile dielectric material having an outer diameter onlyslightly less than the diameter of a corresponding one of said supportbody passages and is positioned wholly within said support body passagefor protection against damage; means securing each of said contact pinsindividually in said support body but allowing removal in the directionof said second end portion and reinsertion of each contact pinindividually without requiring separation of the blocks of insulatingmaterial; said cylinder of dielectric material having a relatively thinfoil conductive sleeve on the outer surface thereof and a centralthrough bore surrounding said contact pin central portion; saidelectrical ground contact means having surfaces extending into each ofsaid passages and yieldingly engaging the conductive sleeve on saidfilter means; said cylindrical filter means having opposite endsretained inside said support body when inserted for use and beingremovable without requiring separation of the blocks of insulatingmaterial.

2. The electrical connector of clalim 1 wherein said electrical groundcontact means comprises a metal contact plate having resilient tinesextending into each of the openings therein and slidingly engaging theconductive sleeve on said filter means.

3. An electrical connector comprising:

a main support body of insulating material having a plurality ofparallel contact passages therethrough;

a contact pin comprising an elongated conductive body having first andsecond end portions adapted to meet with another contact pin and to besecured to a wire conductor respectively, and an elongated centralportion interconnecting said first and second end portions and beinglocated within a support body passage;

impedance means including a cylindrical body of fragile dielectricmaterial surrounding the elongated central portion of said contact unitand an outer relatively thin foil conductive sleeve on the outer surfaceof said dielectric body; said cylinder of fragile dielectric materialhaving an outer diameter only slightly less than the diameter of acorresponding one of said support body passages and is positioned whollywithin said support body passage for protection against damage;

said contact pin being installable within said body means by insertingsaid first end portion into one end of a passage to move through saidpassage and to partially project from the opposite end thereof and beingremovable by withdrawal in the reverse direction;

means mounting said impedance means for insertion into and removal fromsaid support body;

ground contact means in said body mounted in surrounding, contactingrelationship with said outer conductive sleeve, and making wipingcontact with said outer conductive sleeve during installation andremoval of said impedance means; and

means for releasably locking said contact pin upon insertion of the pinin said passage, said locking means being releasable to permitwithdrawal of said contact pin in said reverse direction.

4. The electrical connector of claim 3 wherein said body includes a pairof blocks having aligned openings defining said passages, and saidground contact means comprises a metal contact plate sandwiched betweensaid pair of blocks, said contact plate having openings aligned withsaid passages in said pair of blocks, and a plurality of angularlyspaced, radially inwardly extending tines in each of said openingsthereof, said tines being curved for wiping engagement with angularlyspaced portions of the outer surface of said outer conductive sleeve.

5. The electrical connector of claim 3 wherein said impedance means hasa central bore into which the elongated central portion of said contactpin extends, and said contact pin further includes a pair of collarslocated at opposite ends of said central portion. said collars havingdiameters larger than the bore of said impedance means.

6. The electrical connector of claim 5 wherein the diameter of saidouter conductive sleeve is approximately the same as the diameter ofsaid collars and only slightly less than the diameter of said supportbody passage, and both of said collars are located in and positioned bythe walls of said support body passage when said contact pin is lockedin said passage.

7. In an electrical connector half that is useful in a two-partconnector system having a plurality of individually removable andreplaceable filtered contact units, said connector half including a mainsupport body comprising a pair of blocks of insulating material securedto each other and having a plurality of aligned contact passagestherethrough; and electrical ground contact means comprising a planarlayer of conductive material sandwiched between said pair of blocks andhaving openings aligned with the passages in said blocks; each of saidfiltered contact units including an elongated contact pin and filtermeans including a cylinder of fragile dielectric material, said contactpin having a first end portion adapted for connection with a matingconnector in the other part of said connector system, a second endportion adapted for connection with an electrical conductor, and anelongated central portion interconnecting said end portions; saidcylinder of fragile dielectric material having an outer diameter onlyslightly less than the diameter of a corresponding one of said supportbody passages and is positioned wholly within said support body passagefor protection against damage; means securing each of said contact pinsindividually in said support body but allowing removal in the directionof said second end portion and reinsertion of each contact pinindividually without requiring separation of the blocks of insulatingmaterial, said cylinder of dielectric material having a relatively thinfoil conductive sleeve on the outer surface thereof and a centralthrough bore surrounding said contact pin central portion; saidelectrical ground contact means having surfaces extending into each ofsaid passages and yieldingly engaging the conductive sleeve on saidfilter means; said cylindrical filter means having opposite endsretained inside said support body when inserted for use and beingremovable without requiring separation of the blocks of insulatingmaterial.

8. In an electrical connector half that is useful in a two-partconnector system having a plurality of individually removable andreplaceable filtered contact units, said connector half comprising;

a main support body of insulating material having a plurality ofparallel contact support passages therethrough;

a contact pin comprising an elongated conductive body having first andsecond end portions adapted to meet with another contact pin in theother connector system part and to be secured to a wire conductor,respectively, and an elongatedcentral portion interconnecting said firstand second end portions and being located within a support passage;

impedance means including a cylindrical body of fragile dielectricmaterial surrounding the elongated central portion of said contact unitand an outer relatively thin foil conductive sleeve on the outer surfaceof said dielectric body; said cylinder of fragile dielectric materialhaving an outer diameter only slightly less than the diameter of acorresponding one of said support body passages and is positioned whollywithin said support body passage for protection against damage;

said contact pin being installable within said body means by insertingsaid first end portion into one end of a passage to move through saidpassage and to partially project from the opposite end thereof and beingremovable by withdrawal in the reverse direction;

means mounting said impedance means for insertion into and removal fromsaid support body;

ground contact means in said body including a plurality of angularlyspaced, radially inwardly directed tines of conductive material mountedin surrounding, contacting relationship with said outer conductivesleeve, and making wiping contact with said outer conductive sleeveduring installation and removal of said impedance means; and

means for releasably locking said contact pin upon insertion of the pinin said passage, said locking means being releasable to permitwithdrawal of said contact pin in said reverse direction.

9. In an electrical connector having a plurality of individuallyremovable and replaceable filtered contact units, a main support bodycomprising a pair of blocks ofinsulating material secured to each otherand having a plurality of aligned contact passages therethrough; andelectrical ground contact means comprising a planar layer of conductivematerial sandwiched between said pair of blocks and having openingsaligned with the passages in said blocks; each of said filtered contactunits including an elongated contact pin and filter means including acylinder of fragile dielectric material, said contact pin having a firstend portion adapted for connection with a mating connector member, asecond end portion adapted for connection with an electrical conductor,and an elongated central portion interconnecting said end portions;means securing each of said contact pins individually in said supportbody but allowing removal in the direction of said second'end portionand reinsertion of each contact pin individually without requiringseparation of the blocks of insulating material; said cylinder ofdielectric material having a conductive sleeve on the outer surfacethereof and a central through bore surrounding said contact pin centralportion; said electrical ground contact means having surfaces extendinginto each of said passages and yieldingly engaging the conductive sleeveon said filter means; said cylindrical filter means having opposite endsretained inside said support body when inserted for use and beingremovable without requiring separation of the blocks of insulatingmaterial, said electrical ground contact means comprises a metal contactplate having resilient tines extending into each of the openings andslidingly engaging the conductive sleeve on said filter means; and saidcontact pin securing means includes an enlarged, resilient, bulbousmember and an annular collar member spaced therefrom by a predetermineddistance, both of said members being located between said first endportion and said central portion of said contact pin; and saidpassageways have a first bore section having a first diametersufficiently large to pass said bulbous and collar members and saidcylindrical filter unit, and a second bore section of reduced diametersufficiently large to pass the first end portion of said contact pin andto allow forced passage of said bulbous member but not said collarmember, said second bore section extending along said predetermineddistance between said bulbous and collar members.

10. The electrical connector of claim 9 wherein the diameter of saidcollar member is substantially the same size as the diameter of thefirst bore section, the second end section of the contact pin has asecond col lar member which has a diameter substantially the same sizeas the diameter of the first bore section so that the contact pin can beeasily inserted and removed by hand, but not wobbling therein or havingappreciable play; and the filter means is positioned between said collarmembers to be thereby removable and insertable concomitantly withremoval and insertion of the associated contact pin.

11. The electrical connector of claim 10 wherein said fragilecylindrical dielectric body has an outer diameter only slightly lessthan the diameter of said support body passage and is positioned whollywithin said support body passage for protection against damage.

12. In an electrical connector having a plurality of individuallyremovable and replaceable filtered contact units, a main support bodycomprising a pair of blocks of insulating material secured to each otherand having a plurality of aligned contact passages therethrough; saidsupport body being enclosed within a metallic housing comprising forwardand rearward portions each having a mounting flange formed integrallywith both of said portions; an electrical ground contact meanscomprising a planar layer of conductive material sandwiched between saidpair of blocks and having openings aligned with the passages in saidblocks; each of said filtered contact units including an elongatedcontact pin and a cylindrical filter means, said contact pin having afirst end portion adapted for connection with a mating connector member,a second end portion adapted for connection with an electricalconductor, and an elongated central portion interconnecting said endportions; means securing each of said contact pins individually in saidsupport body but allowing removal in the direction of said second endportion and reinsertion of each contact pin individually withoutdeleteri- 0 ous effects on said connector; said cylindrical filter meanshaving a conductive sleeve on the outer surface thereof and a centralthrough bore surrounding said contact pin central portion; saidelectrical ground contact means comprising a metal contact plate havingresilient tines extending into each of said passages and slidingly andyieldingly engaging the conductive sleeve on said filter means; saidmetal contact plate having outer peripheral edges which are clampedbetween the flanges of said metallic housing to establish a lowresistance electrical grounding connection between the metal contactplate of the connector and the mounting flange of. said housing; saidcylindrical filter means having opposite ends retained inside saidsupport body when inserted for use and being removable withoutdeleterious effects on said connector.

13. In an electrical connector having a plurality of individuallyremovable and replaceable filtered contact units, a main support bodycomprising a pair of blocks of insulating material secured to each otherand having a plurality of aligned contact passages therethrough; anelectrical ground contact means comprising a planar layer of conductivematerial sandwiched between said pair of blocks and having openingsaligned with the passages in said blocks; each of said filtered contactunits including an elongated contact pin and a cylindrical filter means,said contact pin having a first end portion adapted for connection witha mating connector member, a second end portion adapted for connectionwith an electrical conductor, and an elongated central portioninterconnecting said end portion means securing each of said contactpins individually in said support body but allowing removal in thedirection of said second end portion and reinsertion of each contact pinindividually without deleterious effects on said connector; saidcylindrical filter means'having a conductive sleeve on the outer surfacethereof and a central through bore surrounding said contact pin centralportion; said electrical ground contact means comprising a metal contactplate having resilient tines extending into each of said passages andslidingly and yieldingly engaging the conductive sleeve on said filtermeans, and a pair of metal backing plates which are both thicker thansaid metal contact plate, each of said backing plates having a largesurface area abuttingly engaged with opposite sides of said contactplate and the abutting surfaces extending into close proximity to saidtines; the metal backing plates of the ground contact means extendingradially outwardly around the entire periphery of the insulatingmaterial; and the connector further including an outer casing having asurface portion of electrically conductive material generally in a planetransverse to said contact passages and in parallel facing and abuttingrelation to surface portions of at least one of said metal backingplates which extend beyond the periphery of the insulating material. andmeans establishing a low resistance electrical connection between saidmetal backing'plates and said outer casing; said cylindrical filtermeans having opposite ends retained inside said support body wheninserted for use and being removablewithout deleterious

1. In an electrical connector having a plurality of individuallyremovable and replaceable filtered contact units, a main support bodycomprising a pair of blocks of insulating material secured to each otherand having a plurality of aligned contact passages therethrough; andelectrical ground contact means comprising a planar layer of conductivematerial sandwiched between said pair of blocks and having openingsaligned with the passages in said blocks; each of said filtered contactunits including an elongated contact pin and filter means including acylinder of fragile dielectric material, said contact pin having a firstend portion adapted for connection with a mating connector member, asecond end portion adapted for connection with an electrical conductor,and an elongated central portion interconnecting said end portions; saidcylinder of fragile dielectric material having an outer diameter onlyslightly less than the diameter of a corresponding one of said supportbody passages and is positioned wholly within said support body passagefor protection against damage; means securing eacH of said contact pinsindividually in said support body but allowing removal in the directionof said second end portion and reinsertion of each contact pinindividually without requiring separation of the blocks of insulatingmaterial; said cylinder of dielectric material having a relatively thinfoil conductive sleeve on the outer surface thereof and a centralthrough bore surrounding said contact pin central portion; saidelectrical ground contact means having surfaces extending into each ofsaid passages and yieldingly engaging the conductive sleeve on saidfilter means; said cylindrical filter means having opposite endsretained inside said support body when inserted for use and beingremovable without requiring separation of the blocks of insulatingmaterial.
 2. The electrical connector of clalim 1 wherein saidelectrical ground contact means comprises a metal contact plate havingresilient tines extending into each of the openings therein andslidingly engaging the conductive sleeve on said filter means.
 3. Anelectrical connector comprising: a main support body of insulatingmaterial having a plurality of parallel contact passages therethrough; acontact pin comprising an elongated conductive body having first andsecond end portions adapted to meet with another contact pin and to besecured to a wire conductor respectively, and an elongated centralportion interconnecting said first and second end portions and beinglocated within a support body passage; impedance means including acylindrical body of fragile dielectric material surrounding theelongated central portion of said contact unit and an outer relativelythin foil conductive sleeve on the outer surface of said dielectricbody; said cylinder of fragile dielectric material having an outerdiameter only slightly less than the diameter of a corresponding one ofsaid support body passages and is positioned wholly within said supportbody passage for protection against damage; said contact pin beinginstallable within said body means by inserting said first end portioninto one end of a passage to move through said passage and to partiallyproject from the opposite end thereof and being removable by withdrawalin the reverse direction; means mounting said impedance means forinsertion into and removal from said support body; ground contact meansin said body mounted in surrounding, contacting relationship with saidouter conductive sleeve, and making wiping contact with said outerconductive sleeve during installation and removal of said impedancemeans; and means for releasably locking said contact pin upon insertionof the pin in said passage, said locking means being releasable topermit withdrawal of said contact pin in said reverse direction.
 4. Theelectrical connector of claim 3 wherein said body includes a pair ofblocks having aligned openings defining said passages, and said groundcontact means comprises a metal contact plate sandwiched between saidpair of blocks, said contact plate having openings aligned with saidpassages in said pair of blocks, and a plurality of angularly spaced,radially inwardly extending tines in each of said openings thereof, saidtines being curved for wiping engagement with angularly spaced portionsof the outer surface of said outer conductive sleeve.
 5. The electricalconnector of claim 3 wherein said impedance means has a central boreinto which the elongated central portion of said contact pin extends,and said contact pin further includes a pair of collars located atopposite ends of said central portion, said collars having diameterslarger than the bore of said impedance means.
 6. The electricalconnector of claim 5 wherein the diameter of said outer conductivesleeve is approximately the same as the diameter of said collars andonly slightly less than the diameter of said support body passage, andboth of said collars are located in and positioned by the walls of saidsupport body passage when said contact pin is locked iN said passage. 7.In an electrical connector half that is useful in a two-part connectorsystem having a plurality of individually removable and replaceablefiltered contact units, said connector half including a main supportbody comprising a pair of blocks of insulating material secured to eachother and having a plurality of aligned contact passages therethrough;and electrical ground contact means comprising a planar layer ofconductive material sandwiched between said pair of blocks and havingopenings aligned with the passages in said blocks; each of said filteredcontact units including an elongated contact pin and filter meansincluding a cylinder of fragile dielectric material, said contact pinhaving a first end portion adapted for connection with a matingconnector in the other part of said connector system, a second endportion adapted for connection with an electrical conductor, and anelongated central portion interconnecting said end portions; saidcylinder of fragile dielectric material having an outer diameter onlyslightly less than the diameter of a corresponding one of said supportbody passages and is positioned wholly within said support body passagefor protection against damage; means securing each of said contact pinsindividually in said support body but allowing removal in the directionof said second end portion and reinsertion of each contact pinindividually without requiring separation of the blocks of insulatingmaterial, said cylinder of dielectric material having a relatively thinfoil conductive sleeve on the outer surface thereof and a centralthrough bore surrounding said contact pin central portion; saidelectrical ground contact means having surfaces extending into each ofsaid passages and yieldingly engaging the conductive sleeve on saidfilter means; said cylindrical filter means having opposite endsretained inside said support body when inserted for use and beingremovable without requiring separation of the blocks of insulatingmaterial.
 8. In an electrical connector half that is useful in atwo-part connector system having a plurality of individually removableand replaceable filtered contact units, said connector half comprising:a main support body of insulating material having a plurality ofparallel contact support passages therethrough; a contact pin comprisingan elongated conductive body having first and second end portionsadapted to meet with another contact pin in the other connector systempart and to be secured to a wire conductor, respectively, and anelongated central portion interconnecting said first and second endportions and being located within a support passage; impedance meansincluding a cylindrical body of fragile dielectric material surroundingthe elongated central portion of said contact unit and an outerrelatively thin foil conductive sleeve on the outer surface of saiddielectric body; said cylinder of fragile dielectric material having anouter diameter only slightly less than the diameter of a correspondingone of said support body passages and is positioned wholly within saidsupport body passage for protection against damage; said contact pinbeing installable within said body means by inserting said first endportion into one end of a passage to move through said passage and topartially project from the opposite end thereof and being removable bywithdrawal in the reverse direction; means mounting said impedance meansfor insertion into and removal from said support body; ground contactmeans in said body including a plurality of angularly spaced, radiallyinwardly directed tines of conductive material mounted in surrounding,contacting relationship with said outer conductive sleeve, and makingwiping contact with said outer conductive sleeve during installation andremoval of said impedance means; and means for releasably locking saidcontact pin upon insertion of the pin in said passage, said lockingmeans being releasable to permit withdrawal of said contacT pin in saidreverse direction.
 9. In an electrical connector having a plurality ofindividually removable and replaceable filtered contact units, a mainsupport body comprising a pair of blocks of insulating material securedto each other and having a plurality of aligned contact passagestherethrough; and electrical ground contact means comprising a planarlayer of conductive material sandwiched between said pair of blocks andhaving openings aligned with the passages in said blocks; each of saidfiltered contact units including an elongated contact pin and filtermeans including a cylinder of fragile dielectric material, said contactpin having a first end portion adapted for connection with a matingconnector member, a second end portion adapted for connection with anelectrical conductor, and an elongated central portion interconnectingsaid end portions; means securing each of said contact pins individuallyin said support body but allowing removal in the direction of saidsecond end portion and reinsertion of each contact pin individuallywithout requiring separation of the blocks of insulating material; saidcylinder of dielectric material having a conductive sleeve on the outersurface thereof and a central through bore surrounding said contact pincentral portion; said electrical ground contact means having surfacesextending into each of said passages and yieldingly engaging theconductive sleeve on said filter means; said cylindrical filter meanshaving opposite ends retained inside said support body when inserted foruse and being removable without requiring separation of the blocks ofinsulating material, said electrical ground contact means comprises ametal contact plate having resilient tines extending into each of theopenings and slidingly engaging the conductive sleeve on said filtermeans; and said contact pin securing means includes an enlarged,resilient, bulbous member and an annular collar member spaced therefromby a predetermined distance, both of said members being located betweensaid first end portion and said central portion of said contact pin; andsaid passageways have a first bore section having a first diametersufficiently large to pass said bulbous and collar members and saidcylindrical filter unit, and a second bore section of reduced diametersufficiently large to pass the first end portion of said contact pin andto allow forced passage of said bulbous member but not said collarmember, said second bore section extending along said predetermineddistance between said bulbous and collar members.
 10. The electricalconnector of claim 9 wherein the diameter of said collar member issubstantially the same size as the diameter of the first bore section,the second end section of the contact pin has a second collar memberwhich has a diameter substantially the same size as the diameter of thefirst bore section so that the contact pin can be easily inserted andremoved by hand, but not wobbling therein or having appreciable play;and the filter means is positioned between said collar members to bethereby removable and insertable concomitantly with removal andinsertion of the associated contact pin.
 11. The electrical connector ofclaim 10 wherein said fragile cylindrical dielectric body has an outerdiameter only slightly less than the diameter of said support bodypassage and is positioned wholly within said support body passage forprotection against damage.
 12. In an electrical connector having aplurality of individually removable and replaceable filtered contactunits, a main support body comprising a pair of blocks of insulatingmaterial secured to each other and having a plurality of aligned contactpassages therethrough; said support body being enclosed within ametallic housing comprising forward and rearward portions each having amounting flange formed integrally with both of said portions; anelectrical ground contact means comprising a planar layer of conductivematerial sandwiched between said pair of blocks and having openingsaligned with the passages in said blocks; each of said filtered contactunits including an elongated contact pin and a cylindrical filter means,said contact pin having a first end portion adapted for connection witha mating connector member, a second end portion adapted for connectionwith an electrical conductor, and an elongated central portioninterconnecting said end portions; means securing each of said contactpins individually in said support body but allowing removal in thedirection of said second end portion and reinsertion of each contact pinindividually without deleterious effects on said connector; saidcylindrical filter means having a conductive sleeve on the outer surfacethereof and a central through bore surrounding said contact pin centralportion; said electrical ground contact means comprising a metal contactplate having resilient tines extending into each of said passages andslidingly and yieldingly engaging the conductive sleeve on said filtermeans; said metal contact plate having outer peripheral edges which areclamped between the flanges of said metallic housing to establish a lowresistance electrical grounding connection between the metal contactplate of the connector and the mounting flange of said housing; saidcylindrical filter means having opposite ends retained inside saidsupport body when inserted for use and being removable withoutdeleterious effects on said connector.
 13. In an electrical connectorhaving a plurality of individually removable and replaceable filteredcontact units, a main support body comprising a pair of blocks ofinsulating material secured to each other and having a plurality ofaligned contact passages therethrough; an electrical ground contactmeans comprising a planar layer of conductive material sandwichedbetween said pair of blocks and having openings aligned with thepassages in said blocks; each of said filtered contact units includingan elongated contact pin and a cylindrical filter means, said contactpin having a first end portion adapted for connection with a matingconnector member, a second end portion adapted for connection with anelectrical conductor, and an elongated central portion interconnectingsaid end portion means securing each of said contact pins individuallyin said support body but allowing removal in the direction of saidsecond end portion and reinsertion of each contact pin individuallywithout deleterious effects on said connector; said cylindrical filtermeans having a conductive sleeve on the outer surface thereof and acentral through bore surrounding said contact pin central portion; saidelectrical ground contact means comprising a metal contact plate havingresilient tines extending into each of said passages and slidingly andyieldingly engaging the conductive sleeve on said filter means, and apair of metal backing plates which are both thicker than said metalcontact plate, each of said backing plates having a large surface areaabuttingly engaged with opposite sides of said contact plate and theabutting surfaces extending into close proximity to said tines; themetal backing plates of the ground contact means extending radiallyoutwardly around the entire periphery of the insulating material; andthe connector further including an outer casing having a surface portionof electrically conductive material generally in a plane transverse tosaid contact passages and in parallel facing and abutting relation tosurface portions of at least one of said metal backing plates whichextend beyond the periphery of the insulating material, and meansestablishing a low resistance electrical connection between said metalbacking plates and said outer casing; said cylindrical filter meanshaving opposite ends retained inside said support body when inserted foruse and being removable without deleterious effects on said connector.